Morphometric analysis of a Hesperian aged Martian lobate scarp using high- resolution data

摘要

Southern highlands of Mars have experienced regional to global scale deformations in the history of its evolution. Deformational structures originated from impact-induced stresses and later viscous relaxation of the impact basin to cooling related global contraction. Here in this study, we investigated an Early Hesperian (Eo-Archean/Paleo-Archean equivalent to the Earth) aged lobate scarp i.e., surface signature of thrust fault, possibly originated because of global contraction. We used 'offset crater perimeter' measurement technique using high-resolution data (both image and DTM) to execute most precise estimation of fault plane slope and length-displacement relationship. The derived range of fault plane slope is much narrower (21-29) than the previously cited 20 to 35 range. Displacement-length ratio (4.51 x 10(-3)) is also unique and lower than the previously evaluated values of lobate scarps from other region (mainly from dichotomy boundary) of Mars. The newly derived results from the morphometric analysis are due the differential stress pattern and the distinct basement rock rheology. Our results highlight the need for more high-resolution estimation of lobate scarps from several regions with the methodology employed in this study to better understand the global Martian early tectonic scenario.